moffatt



(No Model.)

R. R. MOPPATT.

REVERSIBLE SWITCH FOR INCANDESGENT LAMPS.

No. 883,657. Patented Jan. 5, 1886.

N. PETER$ PholoLnhngraphar. Waibinglnn, n c.

UNITED STATES PATENT OFFICE.

RICHARD H. MOFFATT, OF BROOKLYN NEWV YORK, ASSIGNOR TO THE BROOK- LYN ELECTRIC CONSTRUCTION COMPANY, OF SAME PLACE.

REVERSIBLE SWlTCH FOR INCANDESCENT LAMPS.

SPECIFICATION forming part of Letters Patent No. 333,657, dated January 5, 1886:

Application filed February 8, 1882. Serial No. 52,160.

To all whom it may concern..-

Be it known that I, RICHARD B. llIQEEATT, of the city of Brooklyn, county of Kings, State of New York, have invented new and useful Improvements in Reversible Switches for Incandescent Lamps; and I do hereby declare the following to be a full and exact description of the same, reference being had to the accompanying drawings, and to the letters of refer- IO ence marked thereon.

This invention relates to that class of electric lamps known as the incandescent system, in which a carbon conductor of low conductivity is made to give out light by electrical incan- I5 descence within a sealed glass globe that is exhausted of air or in which is placed a preserving gas, and its object is to render the carbon more stable and enduring for the purpose of prolonging the life of the lamp.

In electric lamps, wherein the carbon filament is used to give light by its incandescence, it has been found that a gradual displacement or movement of the carbon itself takes place, to which has been applied the term electrical carrying. This moving or carrying of the carbon molecules is from the negative to the positive end of the carbon, and the amount of such carrying depends upon the resistance of the filament, the elec- 3 tro-motive force between the clamping of the electrodes, the degree of incandescence, and the state of the vacuum, which has been found to be the prolific cause of the final disruption and destruction of the carbons used in high vacuo.

My invention consists in providing an incandescent electric lamp or lamps with a circuit-reverser that will change the course of the electric current within the lamp or lamps every time the circuit is closed therein. It also consists in a novel device for changing the course of the electric current through the lamp by means of the circuit-controller; also, the use of an adjustable reflector, and in the 4 5 devices hereinafter specified.

In the drawings, Figure 1 is a vertical section of a lamp constructed in accordance with my invention. Fig. 2 is a cross-section of the (No model.)

same, taken on the line a: as, Fig. 1. Fig. 3 is a cross-section taken on the line 00 m, Fig. 1. Fig. 4 is a cross-section taken on the line 00 at", Fig. 1. Fig. 5 is a base view of the inner lamp-holder.

Similar letters of reference indicate like parts in the several figures.

A is a glass globe or receiver which is exhausted of air.

D is an inclosed chamber, located in the stem or neck of the receiver, and which is also exhausted of air. a a are leading-in wires, which are fused or cemented to the glass through which they pass. The inner terminals of these wires support the incandescing carbon filament a. The outer terminals of these wires are made to extend upward on the outside of the neck or stem of the receiver A, as shown in Fig. 1.

C is the lampsocket, provided with a central stem or prolongation, C, on the lower end of which is secured a thumb-piece or key, S, by means of which the socket C may be rotated.

D is an outer socket, made so as to receive the lamp socket C. The stem C extends through an opening in the center of the base of the socket-piece D.

The two socket-pieces C and D are made of vulcanite or other suitable non-conducting material.

o is a spiral spring, located between the 80 base of the socket-piece D and-the key S, and is intended to keep the flange on the upper part of the socket C down upon the upper edge of the socket-piece D, in order to insure a good pressure-contact between the metal parts 0 and e.

d d are small inclined projections or lugs, located within the socket D, as shown in Figs. 1 and 4.

d is a spring, one end of which is secured to the base of the socket-piece C, as shownin Figs. 1 and 5.

c is a metallic strip, secured to the under part of the flange of the socket-piece C. A portion of this metal strip extends to the in- 5 ner surface of said socket, and makes contact with the wires or a when the lamp is in position, as shown in Fig. 1. The strips c are made to extend almost entirely around the socket C, as shown in Fig. 3.

e e are metallic studs located upon the edge of the socket D, as shown in Figs. 1 and 2. To these studs are secured wires 6 e, to the outer terminals of which the main or circuit wires are attached.

D is a projecting portion of the socket D, by which the latter is secured to the fixture.

m is a teat or projection on the top of the globe or receiver A. r

m is a metallic reflector having an indentation, n, in its center, by means of which it is held in position upon the teat or projection m,

' as shown in Fig. 1. The reflector is provided with one or more perforations, m, located near its rim. By the use of this adjustable reflector m the light-rays are thrown downward. If desired, the reflector may be used upon the side of the lamp by placing the perforation m" (instead of the indentation n) over the teat or projection m. When the reflector is thus applied to the side of the lamp, the light-rays can be concentrated in a great degree in any desired horizontal direction; or itv may be used to cast a shade instead.

As the metallic plates 0 c extend almost around the circumference of thelamp,as shown in Fig. 3, leaving only asufficient space to insure the breaking of the circuit, the lamp may be turned upon its longitudinal axis, so that the maximum light-giving surface of the carbon filament can be utilized in any desired direction.

In the operation of this invention the lamp is turned by means of the key S upon its longitudinal axis in one direction only. A pawlspring, (1, engaging with projections d d, prevents its rotating in the other direction. In this movement the metal pieces 6 e and c 0 make and break contact, thus completing the circuit through the lamp when the parts cand e are in contact, or breaking said circuit when they are not in contact, as will be understood. As the current always enters through one of the wires 6', it follows that it will travel the carbon filament in a reverse direction every time the lamp is turned to break and close the circuit again. This operation causes a reversal of the current through the carbon filament, and consequently a reversal of the electrical carrying therein, thus preventing to.

a great extent the injurious results that are caused by the current continuously passing through the carbon filament in the same direction.

The details of this invention can be modified and applied in various advantageous ways and still retain the main features for the purposes intended. The means that change or reverse the course of the current through the carbon filament may be made to operate independently of the means used for breaking or closing the circuit.

I am aware that reversing switches have been used in arc lamps, but this I disclaim, as my invention is for use only-in-incandescent electric lamps, in which a fine carbon filament is made luminous in vacuum or in a receiver containing a preserving-gas, the purpose be ing simply to prolong the life of the filament by reversing the course of the electric current through the filament, as described, thus preventing the injurious results caused by the electric disturbance or carrying oft of the molecules of the filament when the current passes always in one direction.

Having thus fully described the nature, construction, and operation of my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination of an electric incandescent lamp and a reversing-switch.

2. An incandescent'electric lamp, substantially as described, provided with means for closing and breaking the circuit that will change or reverse the course of the current through the carbon filament each time the circuit is closed therein, substantially as and for the purpose specified.

3. An incandescent electric lamp provided with means for closing and breaking the circuit through said lamp by rotating or turning the lamp upon its longitudinal axis, substantially as herein specified.

4. An incandescent electric lamp provided with means for breaking and closing the circuit therein, and that will also change or reverse the course of the current through the carbon filament, each time the said circuit is ICO closed in said lamp by rotating the lamp upon 7 bination of the vacuum bulb A, within which is a carbon filament of high resistance forming a continuous unbroken conductor that will give out light by its entire incandescence, with means for changing or reversing the current therein, substantially as described, and for the purpose specified.

6. In an incandescent electric lamp, the combination of the receiver A, rotating socket C, having a central spindle, O, the stationary socket D, and the spring 0, substantially as and for the purpose specified.

7. An incandescent electric lamp provided with means, substantially as described, for permitting the receiver A to be turned upon its longitudinal axis (to a limited distance) without breaking the circuit. for the purpose of utilizing the maximum light-giving surface of the carbon filament in any desired direction, substantially as specified.

8. In an incandescent electric lamp, the combination of the receiverA, rotating socket O, stationary. socket D, the lugs or projections d, and the spring or ratchet 01, substantially as herein specified.

9. In an incandescent electric lamp, the re ceiver A, having a teat m, in combination reflector, m, having a central indentation, n, with an adjustable reflector,m, provided with and one or more perforations,m, substantially IO a central indentation, n, or its equivalent, as and for the purpose specified.

substantially as and for the purpose herein Specified R. R. MOFFATT.

10. In an incandescent electric lamp, the \Vitnesses:

receiver A, provided with a teat-like projec- S. CHIOHESTER,

t-ion, m, in combination with an adjustable E. M. HERRING. 

